You don’t need Mark Zuckerberg to tell you that messaging apps are a big deal…and are probably going to become even bigger. There’s a reason Facebook plunked down $19 billion for WhatsApp last February. According to a recent article in The Huffington Post, WhatsApp has an even higher engagement rate than Facebook, its users sending out an average of 50 billion messages a day.

Never mind Viber, Snapchat, WeChat, and Line….

What does this ever expanding realm of messaging apps mean for your business?

It depends on how you look at it. In her 2014 Internet Trends Report, Mary Meeker suggested that “global messaging ecosystems” could offer businesses the opportunity to connect more personally with consumers. Given just how quickly messaging apps have evolved over the last year and how mobile usage is at an all-time high (and just getting higher), it’s obvious that businesses have a real opportunity to connect with customers through this ever widening vehicle of intimate communication, but the question is how?

Likely you are one of the more than a billion users on Facebook. Take a look at your Facebook messaging app (assuming you have one). What can it do? A whole heck of a lot. Not only can you message your friends, you can share photos with them, transfer money, or order an Uber to pick you up from the airport.

Messaging apps already dominate the Internet communications spectrum for the newest class of users (Millennials), and are beginning to supplant e-mail, SMS, and other communications paradigms of the past for other users as well.

According to a recent article in Business Insider, “Companies like Facebook, Google, Atlassian, and Slack are expanding their messaging apps beyond mere sending text, video, and audio into something a little bit more like an operating system.” As a marketing and communications tool, this “operating system,” or, maybe more appropriately, this ecosystem that knows you intimately is a unique means by which businesses can deliver targeted content and services.

If you thought phone books were outdated, consider how you use those messaging apps on your smartphone. Your messaging app of choice has become your phonebook. It’s intimate, and it’s largely for one-on-one communication.

But that’s not all messaging apps are about, not anymore….

Business Insider recently noted, “Messaging apps are about more than messaging. The first stage of the chat app revolution was focused on growth. In the net phase, companies will focus on building out services and monetizing chat apps’ massive user database.”

How can you take advantage of mobile messaging monetization as a business trying to leverage the brave new world of messaging apps? We’ve got four tips, plus ideas from businesses that are already in the know on this mobile marketing tool:

Create a Value-added Relationship

Consider that, according to Meeker’s report, 36 percent of U.S. adults with smartphones use messaging apps, and nearly half of Millennials do. If you don’t have a business chat profile in Facebook Messenger, WhatsApp, SnapChat, or other mobile messaging app platforms that your target audience uses, get one, and use it regularly (but not to the point of harassment) to engage directly with your customers. Seek to provide a value addition via messaging that is consistent with the value addition your business inherently provides.

Who’s Doing It?

Uber, for example, has become the king of marketing itself through messaging apps. Currently, Facebook Messenger is the most widely used messaging app, and Uber is right there in the chat window, offering you the opportunity to order a ride to the airport in seconds. If you have an Uber account, your payment information, phone number, location, everything is already there. What’s a better value-add than being able to order ride service from your phone?

Users never have to leave

The big advantage to building a business enterprise app that works right inside a mobile app framework (such as those provided by Facebook Messenger, Google, or Slack), is that it can work anywhere you use that messaging app. What’s more, because your app is built on a messaging platform, users can discover you and your business via recommendations from their friends, naturally through their conversations.

Who’s Doing It?

China’s popular Tencent-owned WeChat app offers users the ability to book flights without leaving their chat app. Both online Chinese travel agency LY.com and low-cost air carrier Spring Airlines offer booking service. They also offer check-in service and seat selection—all through WeChat. These services are so popular in-fact, that WeChat is turning into the go-to app for travel transactions.

Pick the app everyone is using

Right now, frankly, we’re all inundated with messaging options, from texting and email to WhatsApp and SnapChat. But if China’s WeChat is any indication, the next big thing is an all-encompassing platform that everyone uses. In the U.S., the most likely candidate is Facebook Messenger with its 700 million users, according to Wired magazine.

Who’s Doing It?

Moneypenny, a virtual assistant service in existence since 2000, is working to take advantage of Messenger’s user base by providing a 24-hour virtual assistant service directly through the Facebook Messenger app.

The message we’re getting at here (pun intended) is this: if you’re seriously considering a foray into building an app within a messaging service, be savvy. Make sure you choose to build in the the messaging app where your target market is spending most of its time—and provide your services wisely.

Millenials Prefer it

This Toronto-based messaging app, also owned by Tencent, is looking to become the “WeChat of the West.” And part of that exploration is determining how to “monetize” messaging apps. Kik’s answer? Promoted Chats, which allow brands to engage one-on-one with followers through video and photo sharing, text updates, and audience feedback.

Who’s Doing It?

Seventeen magazine, Skullcandy, Vans—all are seeing an organic reach of 75 to 80 percent of Kik users, according to Kik’s own data. That data further indicates that some 10 million users have participated in direct conversations with a brand. Perhaps it’s time you became one of the brands that people are connecting with.

So what could your customers do if they had instant access to your service on a mobile messaging app? Start imagining…. Because you really can’t afford not to. Messaging apps are quickly working to supply all of the functions of the mobile Internet without the user ever having to leave his or her chat session. You want to make sure, especially if Millennials are part of your target market, that your business is in the chat window.